Dual density foam core sports board

ABSTRACT

A sports board with an expanded foam core that has a density adapted so the core will receive a solid sheet skin laminated directly thereto without an adhesive layer. The sports board includes a bottom solid sheet skin laminated directly to a bottom surface of the expanded foam core, and a foam top skin laminated to a top surface and heeled to side surfaces of the expanded foam core.

RELATED APPLICATION

[0001] The present application claims priority to co-pending U.S.Provisional Patent Application Serial No. 60/274,735, filed on Mar. 9,2001, and entitled “FOAM SLEDDING DEVICE,” and the complete disclosureis hereby incorporated by reference.

FIELD OF THE INVENTION

[0002] The present invention relates generally to sports boards. Morespecifically, the invention relates to sports boards having twodensities of foam core.

BACKGROUND OF THE INVENTION

[0003] Sports boards are popular for a variety of recreationalactivities, such as snow sledding, body boarding, surfing, etc. Wham-O,Inc.'s BOOGIE BOARD® body boards have been used for years by childrenand adults for sport in ocean surf and to cool off, in an entertainingway, on warm summer days. Similarly, Wham-O, Inc.'s SNOWBOOGIE® sledshave been used for recreation on winter days. Typical sports boards usean expanded foam core, a foam skin laminated to the top and sidesurfaces, and a solid skin having a thin foam backing laminated alongthe bottom surface. An example of a typical sports board is shown inU.S. Pat. No. 4,850,913 to Szabad. The sports board in Szabad includes apolyethylene film laminated to a polyethylene foam sheet to form acomposite film/sheet laminate that is then laminated onto a polyethylenecore. The laminated solid skin improves durability and reduces drag asthe sports board slides along the snow or through the water. One problemwith laminating a solid skin to the bottom of the sports board is thatfor proper adhesion between the solid skin and the core a thinfoam-backing layer must be laminated to the solid skin prior tolaminating the skin to the core of the board. Only after thefoam-backing layer has been applied can the solid skin be laminated tothe bottom surface of the sports board. If a solid skin was laminateddirectly to the core, either the core would blister, or the skin wouldbe too rough and lack toughness.

[0004] Another problem with typical sports boards is the stiffnessrequirements of the core of the board make it uncomfortably firm. Oftenrelatively dense expanded polymer foam must be used as the core tocreate a sports board with the proper stiffness. Using a dense expandedfoam results in an uncomfortably hard board for a user to kneel or lieon.

[0005] Yet another problem encountered in sports boards is that with aslick solid skin laminated to the bottom surface the boards are noteasily steered. A sports board constructed of foam lacks hard sharpedges that can be used to carve turns in the snow or water.

[0006] It would be desirable to develop a sports board that is easy tomanufacture, has the needed stiffness, while including a comfortablesurface for riding, and has a structure that enables greater steeringcontrol. Greater comfort may be achieved through the use a multilayerexpanded foam core, where each layer had a different density. A toplayer may have a softer density for comfort, while a lower layer mayhave a higher density providing needed stiffness.

SUMMARY OF THE INVENTION

[0007] A sports board with an expanded foam core that has a densityadapted so the core will receive a solid sheet skin laminated directlythereto without an adhesive layer. The sports board includes a bottomsolid sheet skin laminated directly to a bottom surface of the expandedfoam core, and a foam top skin laminated to a top surface and heeled toside surfaces of the expanded foam core. The sports board may alsoinclude a dual density foam core.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008]FIG. 1 is a top plan view of a sports board according to oneembodiment of the present invention.

[0009]FIG. 2 is a bottom plan view of the sports board of FIG. 1.

[0010]FIG. 3 is a cross-sectional view of the sports board of FIG. 1,taken along line 3-3.

[0011]FIG. 4 is the partial sectional view of the sports board of FIG.1, showing a handle attached thereto.

[0012]FIG. 5 is the cross-sectional view of a runner of the sports boardof FIG. 1, taken along line 5-5, showing the assembly of a snap rivetwith the runner.

[0013]FIG. 6 is a schematic view of a foam core lamination process formaking a sports board.

[0014]FIG. 7 is a sports board foam core blank having two different foamdensities.

[0015]FIG. 8 is a schematic view of a solid sheet laminating process formaking a sports board.

[0016]FIG. 9 is a plan view of a sports board shape to cut out of alaminated sports board blank.

[0017]FIG. 10 is a cross-sectional view of a sports board, illustratingthe heeling of a top foam skin onto the sports board.

[0018] DETAILED DESCRIPTION AND BEST MODE OF THE INVENTION

[0019] A sports board according to one embodiment of the presentinvention is shown in FIGS. 1 and 2, generally indicated at 10. Sportsboard 10 may be a body board, a sled, or similar recreation board forsliding along water or snow. Sports board 10 includes a body 12 havinghandles 14 and runners 16 connected thereto.

[0020] Body 12 includes a top surface 18, shown in FIG. 1, and a bottomsurface 20, shown in FIG. 2. The top surface of the sports boardincludes handles 14 mounted thereto. The bottom surface of the sportsboard includes runners 16 mounted thereto. Handles 14 may be configuredfor a person to grip when using the sports board. Children, for example,may use sports board 10 for sliding on snow by gripping handles 14 withtheir hands and lying prone on top surface 18 of body 12. Runners 16 maybe configured to aid in steering the sports board while sledding.Children, for example, may steer sports board 10, while sliding downhill on snow, by shifting their weight from side to side causing therunners to dig into the snow and carve a turn.

[0021] As shown in FIGS. 1 and 2, sports board 10 includes four handles14 and four runners 16. It should be understood that other handleconfigurations and runner configurations may be used with the presentinvention. Further, it should be understood that in some applications,such as a sports board for surfing, runners 16 may take the form of finsconfigured to aid in steering the sports board gliding through thewater. The position of runners 16 may be moved according to theactivities for which the sports board is designed.

[0022] Handles 14 are secured to body 12 using snap rivets 22 and strap24. Each strap 24 is threaded through each handle 14 and snap rivet 22is inserted through an aperture (not shown) in strap 24 securing thestrap to body 12 of board 10, as will be further explained below withreference to FIG. 4. It should be noted that handles 14 may bepositioned on body 12 in other locations and that there may be anynumber of handles 14.

[0023] A cross-section of sports board 10, taken along line 3-3 of FIG.1, is shown in FIG. 3. Body 12 of sports board 10 includes a first coresection 26, a second core section 28, a solid sheet bottom skin 30, anda foam sheet top skin 32. First core section 26 has a first densityρ^(l). Similarly, second core section 28 has a second density ρ^(h).First density ρ^(l) is less that second density ρ^(h). First densityρ_(l). may be in the range of around 1.0 pounds per cubic foot (PCF) to1.5 PCF, and preferably first density ρ^(l) may be around 1.2 PCF.Second density ρ^(h) may be in the range of around 1.7 PCF to 3.0 PCF,and more preferably second density ρ^(h) may be around 2.2 PCF. Byhaving a density of 2.2 PCF, core section 28 may be optimized forbonding to skin 30.

[0024] Solid bottom skin 30 may be a solid polymer sheet having a lowcoefficient of friction to enhance the performance of the sports board.Solid bottom skin 30 may be in the range of 6 to 25 mils thick, and morepreferably around 15 mils thick. Solid bottom skin 30 may be made ofextruded polyethylene or other polyolefins. The thickness of skin 30 maybe selected to optimize bonding to second core section 28 and durabilityof sports board 10.

[0025] Foam sheet top skin 32 may be a high-density polymer foam sheethaving a relatively thin thickness. Skin 32 may have a density in therange of about 4 to 10 PCF, preferably 6 PCF, and a thickness in therange of about 0.100 to 0.150 inches, preferably 0.125 inches. Skin 32may be textured and have a tackiness to prevent a rider from slippingoff of sports board 10 while riding.

[0026] In FIGS. 4 and 5, the coupling of handle 14 and runner 16 throughbody 12 is shown. Strap 24 is threaded through handle 14 and secured tobody 12 by snap rivet 22. Strap 24 may be any suitable flexible materialsuch as nylon webbing. Strap 24 includes apertures (not shown) in eachend sized to enable the snap rivet 22 to pass through the end of thestrap. Snap rivet 22 may be adapted to couple with a snap post 34 thatextends upward from runner 16. Snap post 34 includes snap slots 36 thatare configured to engage snap rivet 22 and retain the rivet after it hasbeen inserted into the snap post. As illustrated in FIG. 5, snap rivet22 includes snap segments 38. As shown, snap segments 38 arefrusto-conical shape and are configured to snap into successive snapslots 36 until all the snap segments are completely inserted. As shownin FIG. 4, snap posts 34 are inserted from the bottom of body 12upwardly through apertures in the body. Snap rivets 22 are then insertedfrom the top of body 12 downwardly through the apertures in straps 24and into snap post 34. As snap rivet 22 inserts into snap post 34, snapsegments 38 engage snap slots 36 securing handle 14 to runner 16 throughthe body of sports board 10.

[0027] Runner 16 may be a hard plastic or similar material adapted tokeep sports board 10 tracking along in a single direction. Runners 16further enable a rider to cause the sports board to turn by shifting therider's weight on the sports board enhancing the play value of thesports board. As shown in FIG. 5, runner 16 has a narrow lower endconfigured to keep the sports board on track in the snow, traveling inthe direction pointed by the rider.

[0028] One method of manufacturing sports boards according to thepresent invention is illustrated in FIGS. 6-10. First, two extruded foamcore materials having different densities are laminated together and cutinto sports board blanks, as shown in FIGS. 6 and 7. Second, bottom skin30 is extruded and directly laminated onto the sports board blanks, asshown in FIG. 8. Third, the sports board blanks are cut into the shapeof sports boards and a foam top skin is laminated onto each cut sportsboard, as shown in FIG. 9. Finally, the foam top skin is heeled aroundthe sides of the core completing the sports board.

[0029] In FIGS. 6 and 7, a roll 40 of foam having density ρ^(h)positioned above a roll 42 of foam having density ρ^(l). Foam rolls 40,42 may be closed cell polyethylene foam or other suitable expandedpolymer closed cell foams having the required material properties, suchas density, modulus of elasticity, etc. Both foam rolls 40, 42 feed foampast a heater 44 and into laminating rolls 45 and 47. The foam of roll40 having density ρ^(h) will become the second foam core section 28 andthe foam of roll 42 having the density ρ^(l) will become first foam coresection 26. Heater 44 may be any suitable heater, for example, a radiantheater, a hot air heater, or an infrared heater, etc. Heater 44 producesa heating zone at a temperature of around 700° F. for about a 4 incheslong segment between foam rolls 40 and 42 and laminating rollers 45 and47. Traveling through the heating zone softens the two layers of foam toprepare them for laminating between laminating rollers 45 and 47.Laminating rollers 45 and 47 are heated to a temperature of 375° F. toaid in the laminating process. After the two foam layers have beenlaminated together the laminated material passes over a cooling table 46cooling table 46 allows the two laminated foam layers to harden again.Finally, once the laminated foam layers are sufficiently cooled andhardened they are cut into sports board blanks by cutter 48. Cutter 48may be a flying cutter, or other similar cutter that may be used in acontinuous manufacturing process. Sport board blank 50 is shown in FIG.7, and may have dimensions around 1.0 inch thick, 94 inches long, and 48inches wide. It should be understood that other dimensions for sportsboard blank 50 are contemplated within the scope of the presentinvention. Once sports board blank 50 has been formed it is ready toreceive bottom skin 30.

[0030] Conventional techniques for bonding a solid skin to a foam corerequire the use of a sacrificial layer of thin foam to be laminated tothe solid skin before the skin can be laminated to a thick foam core.The reason for the use of a sacrificial layer has to do with the heatenergy carried by the solid sheet when it is at a bonding temperatureand the insulating property of thick foam sheets. The solid sheetcarries so much heat energy that bonding to a thick highly insulatingfoam causes the heat energy to build up and melt the foam, resulting indistortions in the surface of the sheet. By applying a thin sheet offoam as a sacrificial or adhesive layer to the solid skin the distortionproblem is avoided.

[0031] In FIG. 8, the process for extruding bottom skin 30 andlaminating it onto sports board blank 50 is shown. By using a higherdensity foam core and carefully controlling the temperature of the solidskin a direct lamination process is possible without the above describeddistortion problems. Bottom skin 30 may be extruded out of extruder 52and feed around tension roller 54 and around laminating roller 56.Laminating roller 56 may be temperature controlled to ensure that bottomskin 30 reaches the laminating point at a temperature of approximately375° F. Skin 30 may have a temperature higher than 375° F. when it exitsextruder 52, and therefore laminating roller 56 may have to be chilledto ensure skin 30 contacts sports board blank 50 at the correcttemperature. The density ρ^(h) of the second core section is optimizedto bond directly with bottom skin 30 without distortions. Tension roller54 may move to collect and release slack in extruded skin 30 to maintainan efficient laminating process. Sports board blank 50 should be fedinto the laminating roller 56 with second core section facing upward toreceive skin 30. It should be noted that laminating skin 30 to sportsboard blank 50 may be done prior to cutting the blank. For example,extruder 52 and laminating roller 56 may be used downstream oflaminating rollers 45 and 47 prior to the step of cutting the compositecore material with cutter 48 into sports board blank 50.

[0032] Sports board blank 50 is cut to the size and shape of sportsboard 10 and has foam top skin 32 laminated thereto, as shown in FIG. 9.Blank 50 may be cut using a die cut process or similar method of shapingthe blank to the desired shape of the sports board. Foam top skin 32 maybe laminated using conventional laminating techniques directly to coresection 26 of body 12.

[0033] The last step in the manufacture of body 12 is heeling foam topskin 32 to the sides and edges of body 12, as shown in FIG. 10. Heelingmay be done by hand application of pressure and heat using irons, or asimilar operation. When the heeling process is complete the handles andrunners are attached, as discussed above, and the sports board is readyfor use.

[0034] It is believed that the disclosure set forth above encompassesmultiple distinct inventions with independent utility. While each ofthese inventions has been disclosed in its preferred form, the specificembodiments thereof, as disclosed and illustrated herein, are not to beconsidered in a limiting sense as numerous variations are possible. Thesubject matter of the inventions include all novel and non-obviouscombinations and sub-combinations of the various elements, features,functions and/or properties disclosed herein. Where claims recite “a” or“a first” element or equivalent thereof, such claims should beunderstood to include incorporation of one or more such elements,neither requiring, nor excluding two or more such elements.

[0035] It is believed that the following claims particularly point outcertain combinations and sub-combinations that are directed to one ofthe disclosed inventions and are novel and non-obvious. Inventionsembodied in other combinations and sub-combinations of features,functions, elements and/or properties may be claimed through amendmentof those claims or presentation of new claims in this or a relatedapplication. Such amended or new claims, whether they are directed to adifferent invention or directed to the same invention, whetherdifferent, broader, narrower or equal in scope to the original claims,are also regarded as included within the subject matter of theinventions of the present disclosure.

I claim:
 1. A sports board comprising: an expanded foam core having adensity adapted so the core will receive a solid sheet skin laminateddirectly thereto without an adhesive layer; and a bottom solid sheetskin laminated directly to a bottom surface of the expanded foam core.2. The sports board of claim 1, wherein the expanded foam core includesa first section having a first density and a second section having asecond density, and wherein the second density is adapted to receive asolid sheet skin laminated directly thereto without an adhesive layer.3. The sports board of claim 2, wherein the second density is in therange of 1.7 to 3.0 pounds per cubic foot.
 4. The sports board of claim2, wherein the second density is around 2.2 pounds per cubic foot. 5.The sports board of claim 1, wherein the bottom solid sheet skin has athickness in the range of 6-25 mils.
 6. The sports board of claim 1,wherein the bottom solid sheet skin has a thickness of about 15 mils. 7.The sports board of claim 2, wherein the sports board further includes ahandle attached to a top surface of the board.
 8. The sports board ofclaim 2, further including a set of runners attached to the bottomsurface of the board.
 9. The sports board of claim 2, further includinga handle attached to the top surface through the sports board to arunner attached to the bottom surface of the sports board.
 10. A dualdensity foam core sports board comprising: a first core section having afirst density; a second core section having a second density laminatedto the first core section forming a composite core; a bottom skindirectly laminated to a surface of the second core section forming thebottom of the sports board; and a top foam skin laminated to a surfaceof the first core section and healed onto sides of the composite core.11. The sports board of claim 10, wherein the second density is in therange of 1.7 to 3.0 pounds per cubic foot.
 12. The sports board of claim10, wherein the second density is around 2.2 pounds per cubic foot. 13.The sports board of claim 10, wherein the bottom solid sheet skin has athickness in the range of 6-25 mils.
 14. The sports board of claim 10,wherein the bottom solid sheet skin has a thickness of about 15 mils.15. The sports board of claim 10, wherein the sports board furtherincludes a handle attached to the sports board on the top foam skin sideof the board.
 16. The sports board of claim 15, wherein the sports boardfurther includes a runner attached to the bottom skin side of the board.17. The sports board of claim 16, wherein the runner and the handles areattached to the sports board by snap-rivets and snap-posts passingthrough apertures in the sports board.
 18. A sports board comprising: abody having an expanded foam core covered on a bottom surface by a solidskin and covered on a top and on side surfaces by a thin foam skin; ahandle coupled with the body through a flexible strap member; and arunner coupled with the body, wherein the handle and the runner coupletogether though the body of the sports board by a snap rivet passingthrough the flexible strap member and a snap post receiving the snaprivet.
 19. The sports board of claim 18, wherein the snap rivet includessnap segments configured to engage snap slots in the snap post, andwherein the engagement of the snap segments with the snap slots preventsthe snap rivet from being removed from the snap post.
 20. A method ofmanufacturing a dual density foam core sports board comprising:providing a first foam sheet of a first density; providing a second foamsheet of a second density; laminating the first foam sheet to the secondfoam sheet by applying heat and pressure to form a dual densitylaminated sheet; cutting the dual density laminated sheet into a blank;extruding a polymer sheet and laminating it to the blank to form abottom skin on a bottom surface of the blank; cutting a sports boardshape from the blank; and laminating a foam top skin to a top surface ofthe sports board shape and heeling the top skin to sides of the sportsboard shape.